1. Field of the Disclosure
The present disclosure relates to an organic light emitting diode display device and a method of manufacturing the same, and more particularly, to an organic light emitting diode display device and a method of manufacturing the same that improve lifetime and reduce manufacturing costs.
2. Discussion of the Related Art
Recently, with rapid development of information technologies, flat panel display (FPD) devices having a thin profile and light weight have been pursued. The flat panel display devices, representatively, include liquid crystal display devices and organic light emitting diode display devices. The organic light emitting diode display devices may be referred to as organic electroluminescent display devices. Since the organic light emitting diode display devices do not need an additional light source, such as backlights of the liquid crystal display devices, and have high color reproduction ranges, the organic light emitting diode display devices are thinner and display sharper images than the liquid crystal display devices.
An exemplary organic light emitting diode display devices include pixels, each of which comprises red, green and blue sub pixels and which are arranged in a screen. The sub pixels are defined by crossing of gate lines and data lines. Each sub pixel is independently driven by driving elements including thin film transistors, and the thin film transistors and metallic lines are disposed in a driving element region. At this time, if the thin film transistors and the metallic lines in the driving element region reflect outside light, outer visibility is lowered.
FIG. 1 is a cross-sectional view of illustrating a part of an active matrix type organic light emitting diode display device according to the related art.
In FIG. 1, the organic light emitting diode display device of the related art includes an organic light emitting diode 120 and a polarizer 110 formed on a substrate 101 through which light emitted from the organic light emitting diode 120 is transmitted to the outside. The polarizer 110 minimizes reflection of light from the outside and improves outer visibility. The polarizer 110 includes a linear polarizer 111 and a λ/4 phase retarder 113. The linear polarizer 111 polarizes incident light horizontally or vertically. A first adhesive layer 112 is formed between the linear polarizer 111 and the λ/4 phase retarder 113. And second adhesive layer 114 sticks both the polarizer 111 and the substrate 101. The organic light emitting diode 120 includes an anode electrode 121, an organic light-emitting layer 122 and a cathode electrode 123.
Light from the outside is horizontally and linearly polarized though the linear polarizer 111 and is circularly polarized through the λ/4 phase retarder 113. The circularly polarized light is mostly reflected at the cathode electrode 123 of the organic light emitting diode 120, is vertically and linearly polarized through the λ/4 phase retarder 113, and is dissipated passing through the linear polarizer 111.
When the reflection of outside light is minimized using the polarizer 110, however, less than 45% of light emitted from the organic light emitting diode 120 is transmitted, and more than half of the brightness is deceased. Therefore, if more power is used to compensate the deceased brightness, the lifetime of a light emitting portion is reduced. Also, the polarizer 110 is expensive. Therefore, if the polarizer 110 is used for antireflection, cost competitiveness of organic light emitting diode display devices may be lowered.